3cixty: An innovative way to explore cities

3cixty is a flexible and modular platform that integrates heterogeneous data in a semantic knowledge base and provides a full API ecosystem that affords the rapid development of web and mobile apps. It allows answering complex queries that combine different types of information about events, places, and means of transportation in a city. We describe ExplorMI 360, the first large-scale solution based on 3cixty, which has been developed to support visitors to Milan and Expo 2015. By leveraging services already deployed in smart cities, the application aims to support tourists arriving in a new city in planning their visit, exploring their surroundings, and moving around efficiently.